NSFW Detector is an extension for Mozilla-based Web browsers that makes links with rel=”nsfw” attributes less noticeable. Below are two screenshots of a paragraph of text that contains a few NSFW links; the first image shows how it normally appears, and the second image shows how it appears if you have the extension installed.

You can customize the extension to style NSFW links in any way you choose by specifying CSS styles for both default and hover states.